Cyclones are large areas of swirling air with clouds and precipitation being formed inside.
The diameter of our galaxy is about 100,000 light years; it contains more than 100 billion stars, one of which is our Sun.
Atmospherical nitrogen is bound by bacteria and used by living organisms in the form of various compounds.
Cyclones are large areas of circulating air with clouds and precipitation being formed in its centre.
The ozone layer filters the Sun´s harmful UV radiation, therefore it is indispensable for life on Earth.
Water on Earth is in a continuous state of change. The water cycle includes processes such as evaporation, precipitation, melting and freezing.